题解 | #求解立方根#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        double input = in.nextDouble();
        double num = input >= 0 ? input : -input;

        int top = 0, bottom = 0;
        while (top * top * top < num) {
            top++;
        }
        bottom = top - 1;

        int p1 = 1;
        while(p1 <= 10) {
            double n = bottom + ((double)p1) / 10;
            if (n * n * n > num) break;
            p1++;
        }
        p1 -= 1;

        int p2 = 1;
        double f1 = bottom + ((double)p1) / 10;
        while(p2 <= 10) {
            double n = f1 + ((double)p2) / 100;
            if (n * n * n > num) break;
            p2++;
        }
        p2 -= 1;
        if (p2 >= 5) {
            p1 = p1 + 1;
        }

        System.out.println((input > 0 ? "" : "-") + (bottom + ((double)p1) / 10));
    }
}